1. Field of the Invention
The present invention relates to an insertion shape detecting probe, and more particularly to an insertion shape detecting probe that is either inserted into a treatment instrument insertion channel of the endoscope or secured to the insertion portion of the endoscope, to detect an insertion shape of an endoscope insertion portion.
2. Description of the Related Art
In recent years, an endoscope has been widely used in a medical field and an industrial field. Particularly, an endoscope with a flexible insertion portion allows examination of organs deep inside a body cavity with the insertion portion inserted into a curved body cavity without incising a patient body, and allows treatments and operations such as removal of polyps, if necessary, with a treatment instrument inserted into a treatment instrument insertion channel of the endoscope.
However, manipulative skills are required to smoothly insert an elongated insertion portion of an endoscope into the curved body cavity from, for example, the anus to examine inside a lower alimentary tract. This is because the operator is uncertain about where a distal end of the insertion portion is in the body cavity and what state the insertion portion is in.
The insertion state of the insertion portion of the endoscope may be determined from the location of the distal end of the insertion portion and the bending state of the insertion portion through X-ray radioscopy for detecting the shape of the endoscope in insertion, where the insertion portion includes an X-ray radiopaque portion. However, an endoscope shape detection apparatus using X-ray is large, so that such an apparatus which emits X-ray requires a large examination room.
Further, such an endoscope examination requires the operator to operate the endoscope as well as the X-ray apparatus, placing an additional burden on the operator. Hence, it is not necessarily preferable to detect the insertion state of the endoscope insertion portion by X-ray.
For this reason, conventionally, apparatuses described in the following, for example, as disclosed in JP-A No. 2003-047586 (KOKAI), are proposed. One conventional apparatus includes plural elements which transmit electromagnetic wave, ultrasonic wave, and the like, in an insertion portion of an endoscope; and an external detector which receives a signal transmitted from a transmitting element of the insertion portion, to display an insertion portion shape on a monitor of the detector during insertion of the insertion portion. Another conventional apparatus includes an insertion shape detecting probe which has a magnetic field detecting element, to display an insertion portion shape on a monitor of a detector during insertion of an insertion portion by inserting the insertion portion into a body cavity with the insertion shape detecting probe inserted into a treatment instrument insertion channel provided in an endoscope.
The insertion shape detecting probe that is disclosed in JP-A No. 2003-047586 (KOKAI) includes an elongated core wire that, plural inner sheaths, a connecting-and-securing unit, and an outer sheath. Plural shape detecting elements from which signal lines are extended are secured on the core wire at predetermined intervals. Each inner sheath is arranged at the proximal end portion side of each shape detecting element that is secured on the core wire, and the core wire and the signal lines run through the inner sheaths. The connecting-and-securing unit covers and integrally connects each shape detecting element and each inner sheath that is adjacent to each shape detecting element. The plural shape detecting elements that are integrated with the core wire and the plural inner sheaths are inserted inside the outer sheath. Then, the insertion shape detecting probe detects the endoscope insertion portion shape with high accuracy by inserting the insertion shape detecting probe into the treatment instrument insertion channel of the endoscope and arranging the insertion shape detecting probe therein.
Here, in the insertion shape detecting probe according to JP-A No. 2003-047586 (KOKAI), the plural shape detecting elements (coils) are secured on the elongated core wire with the predetermined intervals, the plural inner sheaths through which the core wire and the signal lines (lead lines) that are extended from each shape detecting element run are arranged at the proximal end portion side of each shape detecting element, and the connecting-and-securing unit covers and integrally connects each shape detecting element and each inner sheath that is adjacent thereto. Consequently, each shape detecting element, each inner sheath, and the signal lines are linearly arranged; therefore, improvement in assembliability and miniaturization of the insertion shape detecting probe is realized.